Driving belt



DRIVING BELT Filed June 14. 1922 m I I I I l l I I I Patented Feb. 5, 1929.

UNITED STATES PATENT; OFFICE;

ABRAHAM, I. FREEDLANDER, F DAYTON, OHIO, ASSIGNOR, BY DIRECT AND MESNE ASSIGNMENTS, OF THREE-FOURTHS TO THE DAYTON RUBBER MANUFACTURING COMPANY, OF DAYTON, OHIO, A CORPORATION OF OHIO, AND ONE-FOURTH TO GENERAL MOTORS RESEARCH COMPANY, OF DAYTON, OHIO, A CORPORATION OF DELAWARE.

DRIVING BELT;

Application filed June 14, 1922. Serial in. 568,155.

This invention embraces an improved driving belt, designed particularly as a fan belt for use in automobiles, and a method of manufacturing or producing such a belt.

That branch of my invention which is embodied in the article or belt consists, essentially, of a belt comprised of a plurality of circumferential membersan inner or compression member, an intermediate or central member and an outer or tension member, each member being fabricated in this wise:

The compression member composed of soft rubber mixed with cotton, wool or other fiber, the fibers preferably running crosswise and Vulcanized.

The centralmember composed of rubberized cord fabric cut straight or parallel to the cords and in a pre-stretched condition, due to having been materially stretched before being 2 combined with the other members.

The tension member composed of rubberized fabric cut on the bias or at an angle.

This results in the completed belt being substantially non-stretchable. As these fabric elements are of different characteristics and as each has a different function to perform when embodied in the complete belt, the percentage or degree of stretch to which each issubjected Will differ from the percentage or degree to which the other are subjected.

That branch of my invention which is embodied in the method of producing this belt consists, essentially, in first fabricating the inner or compression member by mixing 5 with soft vulcanizable rubber, cotton, wool or other fiber, with the fibers positioned essentially crosswise of the sheet or strip; in fabricating the intermediate or central member by rubberizing a sheet or strip of cord fabric, with the cords lengthwise of the sheet or strip; in materially stretching such sheet or stri so'that its stretchabl'ity, when itis embodied in the completed belt, will have been largely or substantially wholly eliminated; in fabricatin the outer or tension member of rubberized fabric cut on the bias; in first winding this compression member on a forming drum or structure; in then winding such central member on the already Wound compression member; in winding such tension member on the already wound central member; and finally in vulcanizing, as by steam heat, the material so fabricated and wound one upon the other.

The result of my invention in its two as pects is a driving belt which is substantially non-stretchable circumferentially; which, because of the construction referred to, notably the combined rubber and fibrous compression or inner member, will grip the walls of any grooved pulle on which the belt isused, and which will rea ily bend and grasp the pulley surfaces without losing that effect by any material subsequent stretching, and yet will be firm and nearly rigid transyersely.

lin the accompanying drawings forming a part of this specification:

Fig. 1 is a diagrammatic view of a tension and windingapparatus used in carrying out my method;

Fig. 2 is a view of a piece of fabric cut on the bias;

Fig. 3 is a like View of a piece of mixed vulcanized rubber and fiber, utilized in form- 6 i]:l% th8 inner or compression member of my Fig. 4 is a sectional View of a winding drum, its spool and a roll of belting thereon;

Fig. 5 is a side elevation of the belt comso plete; and

Fi 6 is a sectional view of the belt showing t e different members.

I will first describe my method because it results in the production of the belt. In this 35 way my invention will be more readily understood.

Referring first to the ap aratus I prefer to employ in carrying out t e stretching and winding steps of my method, the numeral 1 00 designates a roll upon which is wound, first,

a quantity of material which is to comprise the compression member, and when this is consumed then a quantity of the material which-is to comprise the central member, and when this in turn is consumed, then a quantityof the material which is to comprise the tension member. Or there may be, say, three rolls, such as 1, each roll carrying a quantity of the respective materials and each roll in we turn mounted in the machine.

As shown in Fig. 1, the material to constitute the compression member has already been wound on the spool carried by the drum,

5 compression member, the win ing being near- 1y complete, as usually three layers are sufficient. Later in the process the material comprising the tension member will be wound on the central member.

As illustrating the operation of the apparatus employed for winding and tensioning the materials it will be seen that the material comprising the central member, general- 1y designated 2, passes over a guide roller 3, a flattening platform 4, another guide roller 5 and a tension roller 6. The shaft 7 of this latter roller is put under different degrees of friction through a screw 8 and its friction block 9, to cause the roller 6 to revolve with more or less resistance. In this way the required tension for the central and tension members is put upon the material as it is wound upon the spool on the drum.

A drum 10 having a gear wheel 11 is moun ted on a shaft 12 and rotated by an idler gear 13 driven by a driving gear 14 on the shaft 15 of an electric or other motor generally indicated at 16. On this 'drum is fitted a removable spool 17 as best seen in Fig. 4. The

materials are wound directly on this spool,

which is carried by the drum, the spool being removable with them as a whole, as shown also in Fig. 4. A knife, which is utilized in cutting the roll of belting into the individual belts forms another invention independent. of this one and is the subject of an application for a patent filed by Amos Puterbaugh, June 19, 1922, Ser. No. 569,410.

It will now be seen that when the motor is put in motion the several gears will rotate the drum with its spool, so that the different sheets or strips which constitute the respective members of the belt can be wound on the spool, in succession, and each sheet or strip put under the required tension, as determined by the adjustment of the tension device, applicable to each sheet or strip.

Preceding the stretching and winding steps it will be understood that the material for each belt member is fabricated. The compression member is fabricated by mixing soft vulcanizable rubber with fiber, preferably of cotton or wool. This mixing of the rubber and fiber is preferably performed by a rubber mixing mill-a pair of rolls, one of which travels faster than the other. The body of rubber so mixed with thefiber is run through a calender machine which forms it into a sheet in which the fibers are found to tend to position themselves lengthwise of the strip. After the sheet is formed it is out off irrstrips crosswise of the sheet so that the fibers will stand crosswise of the strip. The effect of running the rubber sheet through such calender machine is to deprive it of any real stretchability lengthwise, but leave it unaffected crosswise. When therefore the strips are cut crosswise of the sheet, this lateral stretchability in the sheet becomes longitudinal stretchabilityin the strips.

The central member is fabricated by taking a sheet or strip of cord fabric and rubberizing it in the well known way of rubberizing fabric. The strips are cut so that the cords run lengthwise the strip, sometimes called a straight or parallel cut.

The fabrication of the tension member is done by rubberizing a sheet of fabric cut on the bias, at say an angle of 45 degrees to the warp or lengthwise strands, which are crossed by the Woof. V

The characteristic of the compression member is yieldability as it bends round the pulley. The characteristic of the central member, besides extreme strength, is substantially non-stretchability due to the essential stretchability of the cord fabric having been taken out by the stretching operation which precedes the actual winding. The characteristic of the tension member is also strength.

It will now be seen that my method consists in fabricating, substantially in the manner above described, the material for the inner or compression member, with its quality of yieldability; in fabricating the material for the central member, likewise in the way above pointed out, with its practically nonstretchable uality; in fabricating the mate terial for t e tension member, also in the manner pointed out, so that these two members will resist the tension they are put under in use; in subjecting the material of the central member to a tensioning or stretching operation and in winding the three elements, successively, on the drum, first winding the material of the compression member and properly uniting the ends of enough material to girth the spool; in then tenslonlng and winding the material composing the central member with as many laps as desired, say three, which is preferable; and finally 1n winding the material of the tension member again with as many laps as deslred, preferably three.

When the belt has been thus formed and built up it is in the form of a roll of beltmg material, as best seen in Fig. 4. In this state it is vulcanized by the usual vulcanizing process employed in the manufacture of pneumatic rubber tires. The effect of the vulcanization is to cause the several members or zones, andthe laps of material composmg them, all to run together or unite to make a finished and homogeneous structure.

Referring now to the belt that results from this method, attention is called to Figs. 5 and 6 where the same is illustrated in its complete condition, having been cut or severed 130 from the roll of belting onthe spool. This belt so made has the compression member, the central member and the tension member, characterized by the fact that the compression member is compressible in respect to the rubber ingredient, While the central member is]O practically or substantially non-stretcha le. i

The subject matter of the method herein fully set forth is not claimed in the present case but is reserved to form the basis of another application With method claims which will be filedduring the pendency of this present case.

Having thus fully described my invention, What I claim as new and desire to secure by Letters Patent, is 1. A driving belt comprising a compression member composedof rubber mixed With free fiber, a central member composed of rubberized cord fabric, and a tension member composed of rubberized fabric cut on the bias,

the material of the central member being laid on the compression member and that of the tension member on the central member.

2. In a driving belt structure, comprising a roll of belting consisting of a compression member, a central member and a tension member, the compression member formed of soft rubber mixed with free fiber, the central member formed of rubberized cord fabric and the tension member formed of rubberized fabric, the Whole united and comprising a roll of belting.

3. A driving belt comprising a central member composed of rubberized cord fabric, a tension member composed of rubberized fabric out on the bias, a compression member composed of a mass of free fiberinterspersed in soft rubber, said fibers being so embedded in the rubber as to permit the longitudinal expansion to restrict transverse compression of the compression member.

In testimony whereof, I afiix my signature.

ABRAHAM L. EREEDLANDER. 

